it can be sanded down, but it is a lot of work and messy.

by soaking the ceiling with water for 15 minutes or so and then scraping it off with something like a putty knife. But that sounds like a horrible job; I'd look into hiring somebody to do it. Covering the ceilings with another layer of sheetrock would make them even lower so you're probably better off removing the popcorn and refinishing and painting what's underneath. I have no idea how much any of this would cost.

Popcorn ceilings were a thing during the '80s and I don't know why, unless it was to cover up sloppy drywall work on the ceiling.

There used to be skilled, unionized (in some states) dry-wall applicators. Then builders figured out they could use unskilled laborers to do the job and cover up the sins with texture.

I personally have no hang-ups about popcorn ceilings and would never spend money and make a mess in my house to eliminate them, any more than I rip out the machine serging at the hems of all my clothes and re-hem the garment by hand with an invisible hem stich, the way it used to be done.

Basically spray with water and scrape.

Part of what went into my decision was the fact that there were several canister lights and other light fixtures in the wrong location so I wanted them relocated and the easiest thing to do was cover everything and start over.

Also, I removed a large fireplace that was taking up about 35% of one room.

Definitely hire someone but check their references.

Some of the old paint that 'popcorns' is made from asbestos.

They probably didn't use it. Online it says that it was banned in 1977.

We've dealt with it quite a bit in our old home .

I flip houses so I have seen plenty. I have used a garden sprayer to wet it in sections. Let the water soak in. Then use a texture scraper.

what's that?

It's the handheld tool you use to remove the popcorn texture. You can buy them at hardware stores. I think Target and Wal-Mart have then as well. Mine has an attachable bag to catch the falling debris. Google texture scraper and you can see what it looks like. I haven't been able to post pictures here.

and go from there. If it doesn't it's just a messy, time consuming job. If it does you need to check with your local code enforcement folks and see what the regs are for disposing of it.

These guys came in and I THINK they blasted it off with some kind of sander thing. Then they re did it. I was SO glad when the ceilings were redone. I'm sorry I'm not more help.

Otherwise just spray it with water, let it soak in a few minutes and scrape it off with a 6" putty knife. Cover the floor with plastic to catch the debris.